A society (community) where people live is supported by a wide variety of social infrastructures such as electricity, waterworks, transportation, railways, communications, and buildings. On the other hand, recently growing awareness of ecological problems and urgent energy situations require energy saving in every field of the society. There is much heated debate about how to create a social system capable of saving energy without forcing people to put up with inconveniences in life.
In the conventional social system, the social infrastructures are basically managed and operated independently. In, for example, an electricity infrastructure, energy optimization control on a municipality (city, town, or village), region, or household basis is not implemented yet, not to mention energy saving on a country basis.